From 76177aa280494bb36d7a0bcbda1078d4db717020 Mon Sep 17 00:00:00 2001 From: Ali Labbene Date: Mon, 9 Dec 2019 11:25:19 +0100 Subject: Official ARM version: v4.5 --- Documentation/DSP/html/group__scale.html | 391 +++++++++++++++++++++++++++++++ 1 file changed, 391 insertions(+) create mode 100644 Documentation/DSP/html/group__scale.html (limited to 'Documentation/DSP/html/group__scale.html') diff --git a/Documentation/DSP/html/group__scale.html b/Documentation/DSP/html/group__scale.html new file mode 100644 index 0000000..ffb6abe --- /dev/null +++ b/Documentation/DSP/html/group__scale.html @@ -0,0 +1,391 @@ + + + + + +Vector Scale +CMSIS-DSP: Vector Scale + + + + + + + + + + + + + + + +
+
+ + + + + + + +
+
CMSIS-DSP +  Version 1.4.7 +
+
CMSIS DSP Software Library
+
+
+ +
+
    + +
+
+ + + +
+
+ +
+
+
+ +
+ + + + +
+ +
+ +
+
+Functions
+
+
Vector Scale
+
Basic Math Functions
+
+ + + + + + + + + + + + + + +

+Functions

void arm_scale_f32 (float32_t *pSrc, float32_t scale, float32_t *pDst, uint32_t blockSize)
 Multiplies a floating-point vector by a scalar.
 
void arm_scale_q15 (q15_t *pSrc, q15_t scaleFract, int8_t shift, q15_t *pDst, uint32_t blockSize)
 Multiplies a Q15 vector by a scalar.
 
void arm_scale_q31 (q31_t *pSrc, q31_t scaleFract, int8_t shift, q31_t *pDst, uint32_t blockSize)
 Multiplies a Q31 vector by a scalar.
 
void arm_scale_q7 (q7_t *pSrc, q7_t scaleFract, int8_t shift, q7_t *pDst, uint32_t blockSize)
 Multiplies a Q7 vector by a scalar.
 
+

Description

+

Multiply a vector by a scalar value. For floating-point data, the algorithm used is:

+
        
+    pDst[n] = pSrc[n] * scale,   0 <= n < blockSize.        
+

In the fixed-point Q7, Q15, and Q31 functions, scale is represented by a fractional multiplication scaleFract and an arithmetic shift shift. The shift allows the gain of the scaling operation to exceed 1.0. The algorithm used with fixed-point data is:

+
        
+    pDst[n] = (pSrc[n] * scaleFract) << shift,   0 <= n < blockSize.        
+

The overall scale factor applied to the fixed-point data is

+
        
+    scale = scaleFract * 2^shift.        
+

The functions support in-place computation allowing the source and destination pointers to reference the same memory buffer.

+

Function Documentation

+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
void arm_scale_f32 (float32_t * pSrc,
float32_t scale,
float32_t * pDst,
uint32_t blockSize 
)
+
+
Parameters
+ + + + + +
[in]*pSrcpoints to the input vector
[in]scalescale factor to be applied
[out]*pDstpoints to the output vector
[in]blockSizenumber of samples in the vector
+
+
+
Returns
none.
+
Examples:
arm_graphic_equalizer_example_q31.c, and arm_signal_converge_example_f32.c.
+
+

References blockSize.

+ +

Referenced by arm_dct4_f32(), and main().

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
void arm_scale_q15 (q15_t * pSrc,
q15_t scaleFract,
int8_t shift,
q15_t * pDst,
uint32_t blockSize 
)
+
+
Parameters
+ + + + + + +
[in]*pSrcpoints to the input vector
[in]scaleFractfractional portion of the scale value
[in]shiftnumber of bits to shift the result by
[out]*pDstpoints to the output vector
[in]blockSizenumber of samples in the vector
+
+
+
Returns
none.
+

Scaling and Overflow Behavior:

+
The input data *pSrc and scaleFract are in 1.15 format. These are multiplied to yield a 2.30 intermediate result and this is shifted with saturation to 1.15 format.
+ +

References __SIMD32, and blockSize.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
void arm_scale_q31 (q31_t * pSrc,
q31_t scaleFract,
int8_t shift,
q31_t * pDst,
uint32_t blockSize 
)
+
+
Parameters
+ + + + + + +
[in]*pSrcpoints to the input vector
[in]scaleFractfractional portion of the scale value
[in]shiftnumber of bits to shift the result by
[out]*pDstpoints to the output vector
[in]blockSizenumber of samples in the vector
+
+
+
Returns
none.
+

Scaling and Overflow Behavior:

+
The input data *pSrc and scaleFract are in 1.31 format. These are multiplied to yield a 2.62 intermediate result and this is shifted with saturation to 1.31 format.
+
Examples:
arm_graphic_equalizer_example_q31.c.
+
+

References blockSize.

+ +

Referenced by main().

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
void arm_scale_q7 (q7_t * pSrc,
q7_t scaleFract,
int8_t shift,
q7_t * pDst,
uint32_t blockSize 
)
+
+
Parameters
+ + + + + + +
[in]*pSrcpoints to the input vector
[in]scaleFractfractional portion of the scale value
[in]shiftnumber of bits to shift the result by
[out]*pDstpoints to the output vector
[in]blockSizenumber of samples in the vector
+
+
+
Returns
none.
+

Scaling and Overflow Behavior:

+
The input data *pSrc and scaleFract are in 1.7 format. These are multiplied to yield a 2.14 intermediate result and this is shifted with saturation to 1.7 format.
+ +

References __PACKq7, __SIMD32, and blockSize.

+ +
+
+
+
+ + + + -- cgit